Geographic areas of Houston

The geographic areas of Houston are generally classified as either being inside or outside Interstate 610, known as the "Loop." Inside the loop generally encompasses the Central business district and the "island cities" of West University Place (West U.), Southside Place and a portion of Bellaire. ("Island cities" refers to the City of Houston's practice of annexing around the existing boundaries of incorporated municipalities.)

Other "island cities" include the Memorial Villages — Bunker Hill Village, Hedwig Village, Hilshire Village, Hunters Creek Village, Piney Point Village, and Spring Valley Village.

The outlying areas of Houston, as well as the rest of Bellaire, the Memorial Villages, the airports and the city's suburbs and enclaves are outside the loop. Another ring road, Beltway 8 (also known simply as the "Beltway"), encircles the city another 5 miles (8 km) further out. A third, State Highway 99 or Grand Parkway, has begun construction roughly 10 miles (16 km) beyond the Beltway around the outer suburbs and currently extends from north of Interstate 10/U.S. Highway 90 east of Katy to Interstate 69/U.S. Highway 59 in Sugar Land.

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